In general, in a projection type image display apparatus such as a liquid crystal projector, a lamp is positioned and secured at an optically correct position by mounted it on a costless and accurately molded resin lamp holder.
As a source of light, a high-intensity lamp such as a high-pressure mercury lamp or a metal halide lamp is used. Since this type of lamp is operated at a high temperature, it is cooled by blasting air to it using a fan. (See for example Japanese Patent Application Laid Open No. 2004-14204.)
However, such resin lamp holder can be heated by the lamp to a high temperature, and quickly deteriorated. Hence, it must be cooled by a high-power fan.
Moreover, downsizing of a projection type image display apparatus such as a liquid crystal projector has become increasingly demanded in the art in simultaneous with uprating of the power of the lamp. However, under conventional techniques as mentioned above, it is difficult to do so, since a high-intensity lamp must be effectively cooled by a high-power fan or a large fan to prevent the heated resin lamp holder from melting. Fan noise will increase with the power of the fan.